NEW YORK -- Despite winning four of the last five World Series titles, the New York Yankees never have been content to sit still in the offseason. This was never more apparent than in the winter of 2000, when New York aggressively pursued Mike Mussina, the top starting pitcher on the free-agent market.

After all, when you are the Yankees, anything less than a championship is unacceptable. No one knows that better than General Manager Brian Cashman.

"He was the biggest new addition, and I don't think he missed a beat," said Cashman of Mussina's debut season in the Bronx. "He stepped right in and continued to do what he does best, to be one of the best pitchers in the American League."

The Yankees have tinkered with the makeup of their team each season, though the core group of players remains the same. Cashman (and former GM Bob Watson before him) utilized the First-Year Player Draft, trades and free agency to assemble a group of players that will go down as one of the great Yankee teams of all-time.

The common perception is that the Yankees have simply outbid teams in smaller markets for the top-flight free agents, but that couldn't be further from the truth. Of the 25 men on the playoff roster, Mussina is the only big-money free agent of the bunch. The rest were acquired through the First-Year Player Draft, trades or signed as non-drafted free agents.

The foundation of Joe Torre's championship teams have included Derek Jeter, Andy Pettitte and Jorge Posada, each of whom were chosen in the draft. Other cornerstones, such as Mariano Rivera, Bernie Williams and Orlando Hernandez, came to the Yankees as undrafted free agents, showing New York's talent for scouting international players.

But several key Yankees, including Paul O'Neill, Tino Martinez, Scott Brosius, Roger Clemens and Chuck Knoblauch, were acquired via trade, and that was the route that Cashman took this season to fix what he deemed broken.

While the look of this year's AL East championship team is very similar to those of the past three seasons, a closer look shows that it is a very different team than the one that left Spring Training at the end of March.

Sure, the starting lineup looks the same, but nearly one-third of the 25-man playoff roster was not wearing pinstripes when the season started six months ago.

Coming out of Spring Training, neither Torre nor Cashman felt that the bench and bullpen had the depth or experience to make a legitimate run at a fourth consecutive title, so the Yankees underwent a season-long metamorphosis.

The biggest question was whether New York would find an adequate replacement for Jeff Nelson, the right-handed set-up man who signed as a free agent with the Seattle Mariners in the offseason. Early on, the answer appeared to be no, as Mike Stanton and Mariano Rivera were on pace to shatter their respective career-highs in innings pitched. Ramiro Mendoza returned from a shoulder injury, but Torre did not have many arms in the bullpen that he trusted to get crucial outs.

In the final days of June, Cashman supplied Torre with a pair of hard-throwing right-handers in Jay Witasick and Mark Wohlers, giving the manager more options in the late innings.

"We have pretty good balance right now," Torre said. "We're finding out that Witasick better serves us by coming in for a piece of an inning or an inning. With Wohlers, he just takes the ball and goes after it. It's nice to have given them different situations to pitch in. Witasick can come in and get a strikeout, similar to what Nellie did for five years. I'm very pleased with the moves, because I think they gave us a lot of balance and took pressure off Mendoza and Stanton."

June also saw the addition of some role players, as New York picked up Devil Rays castoff Gerald Williams, promoted backup catcher Todd Greene from Triple-A Columbus and acquired utility infielder Enrique Wilson from the Pirates for a minor-league pitcher.

With the exception of rookie second baseman Alfonso Soriano, all of New York's everyday players have been on at least one of the Yankees' championship teams. Many others, from Mussina to the midseason acquisitions, have not had that experience, and that can serve as a driving force for the regulars -- helping their teammates reach the promised land.

"Look across the room, and you'll see some guys that have never experienced postseason play and some that don't have rings on their fingers," said Roger Clemens, who came to the Yankees without a championship ring in 1999. "That's incentive enough for some of us, to go help these guys get a ring. I still remember my first day here, when the 1998 team got their rings. Each guy came through and said 'These are nice, but there's room for another diamond.' That was great to hear, especially in my situation, where I had been working for 16 years to get a ring."

No one wants that ring more than Mussina, who said his biggest motivation for signing with the Yankees was the opportunity to add a World Series title to his impressive resume.

"I came to New York with the hope that we'd have the chance to get there. We're one of the eight teams left and we're going to try to make a run at it," Mussina said. "I'm as ready as I'm ever going to be. We'll go take our shot at it."

Mussina may be the difference-maker for the Yankees, as he enters the postseason as the Yankees' hottest pitcher. He finished the season 17-11, but was 6-1 with a 1.28 ERA over his last nine starts.

"Mike got better as the season went on," Cashman said. "He's had an unbelievable season, but he's had a better second half -- and his first half was pretty good."

This may be New York's last hurrah with this group of players. O'Neill, Martinez and Brosius are free agents, and there is no guarantee that any of them will return next season. The Yankees will do what is necessary to fill their spots should they leave, meaning that the team could have a different look next season.

Then again, what makes that different from any other season? That's the Yankee way.